hi
I am doing a lot more work at the moment where we are operating everything from the foh desk (due to either lack of budget or space on stage)
But I am having problems with the aux send down the Multicore my problem is that my aux sends are unbalanced

I am then going into a 31 band eq at the stage before the amp but am still getting a hum across the monitors?
I was wondering if I should be looking to convert the signal to a balanced one before I send it down the Multicore and if so what should I be looking at to do this ??

You could just use a DI box to balance the signal before sending it down the multicore.
Also you should check that the power on the stage is on the same phase as the power FOH

Is it a jack send? if so try putting it through a DI box to balance it... I'v never tried this, but may do now you've mentioned it.

OK ill try a passive di (didn't think about that)
I no the power is on the same phase as I run everything from my own distro

Beat me to it but same suggestion

Assuming the input to the Eq at the stage end is balanced,you'll only need to balance the output of the mixer. If not, you'll need to balance the input at the stage end as well. You could always try these fifteen quid beauties from our friends at Behringer...
http://www.behringer.com/HD400/index.cfm?lang=ENG

Slightly off topic, but the aux out is unbalanced? Is this the norm on desks or just this one. I haven't got the manual to hand, but I've always thought my behringer desk ( euro rack ub2222fx- pro ) was balanced on all outputs?
baz.

Many cheaper/smaller desks will have unbalanced aux sends. Most though, will have balanced outputs. Your desk aux sends are unbalanced.

According to the Behringer spec sheet, Aux sends on the UB2222FX are unbalanced quarter inch TS connectors. Strangely, the Aux returns are balanced though. Check out this URL http://www.behringer.com/UB2222FX/index.cfm?lang=ENG and click on "spec sheet" on the right hand side for full details.

Alas, unbalanced Aux sends are all too common on economy mixers.

Bob

Does the graphic you are using have a balanced output and do the amps have balanced ins? If so, move the graphic to FOH and use that to balance your signal.
Cost: zero! Now there's an unusual thing!

Who helpfully state "The sound quality may diminish within the range of powerful broadcasting stations and high-frequency sources. Increase the distance between the transmitter and the device and use shielded cables for all connections".

Looks like you don't get much in the way of RF shielding ;-)

If the OP has balanced outs on his graphics, relocating these at FOH would help solve the problem (assuming the amps have balanced inputs).

I would think that the 'warning' is a bit of 'belt and braces' on the part of the manufacturer - if you're getting that kind of problem with a line-level signal inside an earthed metal box, then you've probably got bigger problems to worry about :-)

But I agree that moving the graphic could be a far more elegant solution

You can only benefit from having the graphics up at FOH anyway? I know as a rule they'd be in monitorworld but surely when run from FOH you'll need them there for easy control when setting up.
So I'll go with the last few posts, move the graphics to FOH, use an unbalanced lead from desk to graphic. and a balanced line down the multicore to the amps (providing their inputs are balanced).


Rob

Cheers for that guys.

I was thinking about getting some balanced cables for the aux sends, but as it transpired I've switched to a full stereo rig, which means I'm going in to the digitech quads and then to the desk. gorgeous full sound, but this is colinskuse's post so back to the plot.
baz

the amps do have balanced inputs and I no its not a problem with the line level problem I no its only a problem wen sending down the multi as if I go direct from the desk in to the graphic then the amp all is OK

in respect to moving the graphic it will be running then down a 50m multi is this advisable as I have been told in the past that this isn't

Yes this will be fine and is more common than the way you have it set up at the moment.